1. Technical Field
The present invention relates to a useful new curable resin composition for use in water based paints. In particular, it relates to a curable resin composition, of particular use in paints, which has excellent weather resistant properties, and furthermore provides excellent curability, and gives excellent resistance against solvents, chemicals and water. The primary constituents of this curable resin composition include; a water based product obtained by dispersing or dissolving in water, a tertiary amino vinyl polymer, or vinyl polymer containing both tertiary amino and acidic functionalities which has been neutralised by an acidic compound, or alternatively, an acidic vinyl polymer, or vinyl polymer containing both tertiary amino and acidic functionalities which has been neutralised by a basic compound, and a compound containing both epoxy and hydrolysable silyl functionalities.
2. Description of the Prior Art
Due to recent worldwide demand for increased environmental conservation measures and improvements in workplace conditions, it is becoming necessary to move away from current organic solvent based paints, to paints which release less organic solvent into the atmosphere. In addition, from an energy conservation point of view, paint resins which will cross link at room temperature would be most attractive.
In order to fulfil these requirements, aqueous emulsions of a copolymer formed from an unsaturated monomer of the ethylene family and a primary or secondary amino alkyl (meta) acrylate, with an epoxy silane coupling agent have been proposed (Japanese Patent Application, First Publication, No. Sho 61-28543), but the cured coating film from such compositions tends to be inferior in terms of its weather resistant properties.
Furthermore, water based adhesive compositions formed by combining an epoxy silane coupling reagent, with a water based polymer formed by emulsion polymerisation of a vinyl monomer containing either carboxyl or tertiary amino functionalities (U.S. Pat. No. 4,077,932), or alternatively water based coating compositions for use with paper or textiles (Japanese Patent Application, First Publication, No. Hei 1-96270) have also been proposed, but the surface obtained from such compositions, in all cases, is inferior, either in terms of water and solvent resistance, or in terms of surface appearance.
Moreover, alkali soluble adhesive compositions formed by combining a surface active agent and an epoxy silane coupling agent, with an aqueous solution of a carboxyl vinyl polymer, which is produced either by polymerisation of a single carboxyl vinyl monomer, or by copolymerisation of two or more different carboxyl vinyl monomers, have also been proposed (Japanese Patent Application, Unpublished, No. Hei 6-41504), but the surface formed from such compositions is inferior, particularly in terms of its resistance to water and alkalinity.
The limitation then, of the aforementioned water based resins of vinyl polymers containing either emulsifiers or surface active reagents is that the resultant surfaces inevitably lack resistance to water and other solvents.